Antibacterial activities of rhubarb extracts against food-borne bacteria and the bioactive compounds

In this study,antibacterial activities of rhubarb against E. coli,Salmonella and S. aureus were studied.Preliminery screening indicated that rhubarb root ethanol extract,and the chloroform fraction was found to be the most active fraction of the crude extract. Five major compounds were identified from the chloroform fraction by UPLC-MS/MS,namely emodin,aloe-emodin,rhein,physcion and chysophanol. Among these five compounds,rhein showed the greatest antibacterial activities against E.coli and Salmonella with the MIC as 125 and250 μg/m L,MBC as 250 and 500 μg/m L. Emodin showed the greatest antibacterial activities against S. aureus.with the MIC and MBC as 62.5 and 125 μg/m L.